Locking clamp



Juli; 24, 1956 E. K. JOHANSEN LOCKING CLAMP Filed March 7, 1952 IN V ENTOR.

J E INAR K. JOHANSEN I ATT'YS LOCKING CLAMP Einar K. Johanseu, Oak Park,111., assignor, by rnesne assignments, to U. S. Industries, Inc., acorporation of Delaware Application March 7, 1952, Serial No. 275,428

2 Claims. (Cl. 113-49) This invention relates in general to lockingdevices, and in particular to a locking device or clamp for holdingmachine parts together such as, for example, for holding a die memberagainst the slide of a metal working press.

In metal working or forming presses of the character wherein a die issecured to the underside of a slide and is caused to move downwardlyagainst a metal blank supported by another die on the bed of the press,it has been customary heretofore to secure the die to the slide by meansof bolts or other similar fastening means. This may be done in arelatively simple and expeditious manner if a single action press isinvolved. On the other hand, double action presses present a seriousproblem from the standpoint of reaching the bolts which secure the dieto the inner slide.

In double action presses an outer slide is caused to move downwardly andhold the blank in place on the die on the bed after which the innerslide moves downwardly with the die fixed thereto for a drawingoperation. Present practice has been to provide openings or windows inthe sides of the outer blank holder slide to enable the die setter oroperator of the press to obtain access to the inner slide for thepurpose of placing bolts thereon and securing the die thereto.

It is customary to form T-slots in the underside of the inner slide forthe reception of the bolt heads. The bolts will thereupon extend belowthe undersurface of the inner slide and present themselves for insertionthrough holes in an upper flange of the die as the die is movedvertically upwardly by hand whereupon nuts are screwed onto the bolts tohold the die in place.

It is not difficult to insert the bolts in the T-slots because they canbe arranged opposite the openings or windows in the blank holder slide.A serious problem, however, is presented in reaching through the windowand below the flange on the die to apply the nut. Such an operation isusually performed blindly by the operator and thus consumes considerabletime in aflixing the die to the slide.

The present invention is designed to overcome the disadvantagesenumerated above and enables the die to be fixed to the slide quicklyand easily, thus saving time in setting the die. Furthermore, the deviceembodying the present invention is designed to be utilized in connectionwith the conventional T-slot which is already present on the draw slideand to utilize also the flange at the upper part of the die.

It is therefore a principal object of the present invention to provide alock or clamping device to facilitate the securing in place of a die tothe inner slide of a double action metal working press.

Another object of the invention is to provide a locking device forlocking a die member to the inner slide of a double action metal workingpress wherein the T-slot already present in the inner slide may beutilized for supporting the device which acts in cooperation with aflange on the die to clamp the die in place against the underside of theslide.

tates Patent A further object of the invention is to provide a lockingdevice for locking a die to the underside of a draw slide wherein apivotally mounted lever supported on the slide is caused to be rotatedso that one arm thereof will clamp the die to the slide by cooperationwith a flange on the die.

Still another object of the invention is to provide a locking device forlooking a die member to a draw slide wherein one arm of a pivotallymounted lever is caused to have a clamping action against a flange onthe die and wherein the lever is caused to rotate to its clampingposition by means of a wedge arrangement on the other arm of the lever.

A still further object of the invention is to provide a locking devicefor looking a die member to the draw slide of a metal working presswherein a pivotally mounted lever has one arm thereof operable as aclamping device and wherein the other arm thereof is operable to rotatethe lever by means of a wedge arrangement actuated by a screw threadeddevice supported by the draw slide.

Other objects and advantages of the invention will become apparent uponreading the following description taken in conjunction with theaccompanying drawing in which:

Fig. 1 is a sectional view through a portion of a draw slide and diefixed thereto showing the device of the present invention in sideelevation;

Fig. 2 is an end elevational view of the locking device shown in Fig. 1;

Fig. 3 is a horizontal sectional view taken along the plane of line 3--3of Fig. 1; and

Fig. 4 is a fragmentary elevational view of the device shown in Fig. 1illustrating a modification thereof.

Referring now more particularly to the drawing, the draw slide, or aportion thereof, is indicated by the numeral 1 and the T-slot in thelower part of the draw slide is generally indicated at 2. There will beprovided a plurality of such T-slots extending inwardly from the outeredge of the draw slide and there may be as many of these slots as may benecessary, depending upon the size of the press and the number oflocking or clamping devices which it may be necessary to use for lockingthe die in position.

For illustration purposes, only one such T-slot is shown, it beingunderstood that the device embodying the present invention is adaptedfor use in each one of the slots as may be necessary. Each T-slotincludes a horizontal portion 3 and a downwardly extending portion 4opening through the bottom side of the draw slide. Since double actionpresses and their construction in general are well known, it has notbeen deemed necessary to illustrate the relative position of the outeror blank holder slide.

The die which is adapted to be mounted on the underside of the drawslide is generally indicated by the numeral 5 and is provided with aflange 6 at the upper part there of which extends laterally outwardlytherefrom on as many sides as may be necessary.

The locking clamp embodying the present invention consists of a mainsupport or body portion 7 also generally T-shaped and adapted to bereceived in the T-slot 2. The upper part of the support 7 may extendlaterally and be received by the upper portion 3 of the T-slot. Thesupport 7 has a downwardly depending portion 8 which 1s narrower thanthe upper part thereof and passes downwardly and outwardly through thelower part 4 of the T-slot 2.

A pin 9 is received in the lower part of the depending portion 8 and isadapted to pivotally or rotatably receive a lever 10. This lever 10 isrelatively wide as may be seen more clearly in Fig. 2 and has a centralrecess 11 therein between the sides thereof to receive the lower curvedend 12 of the depending portion 8 on the support. It will thus far beevident that the lever 10 plvoted on the pin 9 will be supported orsuspended from through the window of the outer the support 7 and will befree to rotate or have a pivotal action thereon.

The lever 10 is provided with an arm 13 which extends generally inwardlyof the press and terminates in a generally arcuate portion 14 adapted tobear upwardly against the underside of 'the flange 6 when in operativeposition as illustrated in Fig. 1.

Another arm 15 is formed integral with the lever 10 and extendsgenerally outwardly therefrom and is provided with a substantiallycentrally located narrowed wedge portion 16 at the upper part thereof.The part 16 is necessarily made more narrow so that it may be receivedwithin the vertical portion 4 of the T-slot in the draw slide. The uppersurface of the narrow wedge part 16 slopes downwardly and inwardly ofthe press as at 17 thereby providing a wedge surface thereon. It will beevident thus far that a downward pressure on the arm 15 will cause acounterclockwise rotation of the lever '10 thus urging the arm 13upwardly against the underside of the flange 6 on the die 5. Whensuflicient pressure is exerted on the lever 10 the result will be toclamp tightly the die against the underside of the draw slide.

The mechanism which is provided to exert the necessary pressure againstthe arm 15 includes an elongated bolt or similar threaded member 18which extends outwardly in a generally horizontal position from thesupport 7 and at the upper part thereof. The inner end of the threadedmember 18 has fixed thereto a generally circular detent member 19provided with a plurality of axially extending grooves 20 on theperiphery thereof. immediately below the detent 19 and within the bodyof the support 7 there is provided a recess 21 having a coil spring 22therein for the purpose of urging upwardly a ball retaining member 23.The arrangement is such that when the screw 18 is rotated causingrotation of the detent 19, the ball 23 will be urged upwardly by spring22 and will seat in one of the grooves 20 to thereby prevent inadvertentrotation of the screw.

The inner end of the opening in the body 7 which receives the screw 18is enlarged as at 24 providing an annular shoulder 25 against which thecircular detent 19 abuts. This enlarged opening 24 is then flaredoutwardly as at 26 and opens rearwardly of the support 7 to receive ascrew threaded plug 27 thereby holding the screw member 18 against axialmovement.

A movable wedge member 28 is of generally T shape and is received by theT-slot This wedge member 28 is provided with a threaded openingtherethrough to threadedly receive the screw member 18. The lower partof wedge member '28 is narrowed to be received by the lower part of theT-slot and terminates so that its undersurface is arcuate as illustratedby the numeral 29 or may terminate in any other suitable manner -in away which will cooperate with the downwardly and inwardly slopingsurface 17 on the lever 10.

It will be evident that upon rotating the screw member '18 in the properdirection, the movable wedge member 28 will be caused to move outwardlyor toward the left as viewed in Figs. 1 and 3 since it cannot rotate byreason of its fit within-the 'T-slot. Such outward movement of the wedgemember 28 will cause the lever 10 to be rotated in a counterclockwisedirection about the pivot pin 9. This results from the contact betweenthe undersurface 29 on the wedge member 28 and the upper sloping surface17 onthe arm 15 of the lever 10. This wedging action between the members28 and 10 will urge the arm 15 downwardly-and the arm 13 upwardlyagainst the underside of the flange 6 on the dre S thereby locking orclamping the die against the underside of the draw slide 1. a

Any suit-able means may be provided to enable the screw 1-8 to beconveniently rot'at'ed by merely reaching blank holder slide. In the'form of the invention-shown'herein, the outer end of screw 18 isprovided with a nonacircula'r end so adapted to receive a tool such as:a socket-w-rench.

In assembling the device of the present invention the screw 18 with thecircular "dete'nt 19 dried to one end thereof is inserted through theopening in the support 7 from the right-hand side thereof as viewed inFig. 1. The spring 22 and ball 23 will have previously been inserted inthe recess 21. The plug 27 may then be placed in the opening 26 therebyto hold the screw 18 against axial movement. When the screw 18 isinserted in the support 7 the longitudinal movement thereof will belimited by the detent 19 abutting against the annular shoulder '25. Themovable wedge member 28 may then be screwed onto the member 18 to apoint thereon such that the lever 10 will have a relatively free pivotalmovement so that the arm 13 thereof may be moved downwardly a shortdistance. The entire assembly may then be inserted in the T-slot 2 ofthe draw slide and the die placed in position against the underside ofthe draw slide. The die setter or machine operator may then reachthrough the opening in the blank holder slide which will be opposite theend of the T-slot and place a socket wrench or other suitable tool 'onthe socket end 30 of the screw and turn the screw so that the wedgemember 28 will move outwardly thereon. As the member 28 moves outwardly,it will "force arm 15 downwardly by a wedging action and will urge arm13 upwardly against the underside of the flange '6 on the die until thedie is firmly clamped in place and locked against movement.

It is thus obvious that the operator or die setter has avoided theinconveniences of reaching through the opening of the blank holder slideto the flange on the die in an attempt to place a nut on the lower endof a bolt passing therethrough. The present invention has-the advantagethat the operator can easily apply a tool to the end of screw 18 and canthereby see what he is doing. Another advantage arising out of the useof the present construction is the speed with which a die can be fixedin place. Rotating the screw 18 to a position where it will cause thelever 10 to clamp the die in place can be accomplished more rapidly thanapplying a nut to a bolt which cannot be seen.

Fig. 4 of the drawing illustrates a slight modification from that shownin Fig. 1 wherein the underside of the flange 6a on the die 5 isprovided with arcuate surface as indicated at 31. -In some instancesthis may prove to be advantageous in more firmly locking the die inplace by reason of the cooperation between the curved surface 14 on thearm 13 and this arcuate portion 31 of the flange 6a.

In either event the advantages of the construction will be the same. itwill also be clear that instead of the curved nndersurface 29 of thewedge 28 this surface could be sloping in a manner complementary to thesurface 17, if so desired. The specific shapes of the surfaces 17 and 29is unimportant as long as the relative movement between the two surfaceswill have a wedging action.

Changes may be made in the form, construction and arrangement of partsfrom those disclosed herein with- ;outin any way departing from thespirit of the invention :or sacrificing an; of the attendant advantagesthereof, provided, however, that 'suchchanges fall within the scope ofthe claims appended hereto.

The invention "is hereby claimed as follows:

1. A locking clamp for securing a die to the slide of a metal workingpress, comprising a -T-s hap ed support adapted to be received by acorresponding T -sh aped slot in the slide, said support including .aleg member and a cross member, a lever pivotally mounted on ftheend ofsaid leg member, said lever having arms extending outwardly in oppositedirections from the pivotal point thereof and oneof said arms beingadapted to move in adireeti'on to engage a portion of a die and clampthedie to the slide, the other of said arms havinga cam portion at the endthereof adapted to be received by the leg of said slot, an elongatedscrew member having a cylindrical end extending solely through the crossmember of said support and longitudinally of the slot and rotatabletherein, means to hold said end against longitudinal movement withrespect to said support, a lever operating member threadedly engagingsaid screw member and movable longitudinally thereof into contact withthe cam portion on said other arm, thereby to urge said one arm intoclamping engagement with the die, said operating member having aconfiguration complementary to the T-shaped slot and confined thereinagainst rotation.

2. A locking clamp for securing a die to the slide of a metal workingpress, comprising a T-shaped support adapted to be received by acorresponding T-shaped slot in the slide, said support including a legmember and a cross member, a lever pivotally mounted on the end of saidleg member, said lever having arms extending outwardly in oppositedirections from the pivotal point thereof and one of said arms beingadapted to move in a direction to engage a portion of a die and clampthe die to the slide, the other of said arms having a cam portion at theend thereof adapted to be received by the leg of said slot, an elongatedscrew member having a headed cylindrical portion extending through thecross member of said support and longitudinally of the slot androtatable therein, means cooperating with said headed portion to holdsaid screw member against longitudinal movement with respect to saidsupport, a lever operating member threadedly engaging said screw andmovable longitudinally thereof into contact with the cam portion on saidother arm, thereby to urge said one arm into clamping engagement withthe die, said operating member having a configuration complementary tothe T- shaped slot and confined therein against rotation and a' springloaded detent means on said support engageable with the headed portionof said screw member for retaining the latter in adjusted position.

References Cited in the file of this patent UNITED STATES PATENTS1,060,477 Meyers Apr. 29, 1913 1,348,658 Nelson Aug. 3, 1920 1,350,097Glover Aug. 17, 1920 1,414,839 Stuarts May 2, 1922 1,499,843 PetersonJuly 1, 1924 1,801,222 Cayo Apr. 14, 1931 1,982,488 Weber Nov. 27, 19341,995,206 Geissbuhler Mar. 19, 1935 2,341,564 La Pierre Feb. 15, 19442,390,022 Wood Nov. 27, 1945 2,413,943 Bolduc Ian. 7, 1947 2,482,708Gordiner Sept. 20, 1949 2,519,157 Stacey Aug. 15, 1950 2,577,029Moorehead Dec. 4, 1951

